Changes with nginx 0.8.37 17 May 2010

    *) Feature: the ngx_http_split_clients_module.

    *) Feature: the "map" directive supports keys more than 255 characters.

    *) Bugfix: nginx ignored the "private" and "no-store" values in the
       "Cache-Control" backend response header line.

    *) Bugfix: a "stub" parameter of an "include" SSI directive was not
       used, if empty response has 200 status code.

    *) Bugfix: if a proxied or FastCGI request was internally redirected to
       another proxied or FastCGI location, then a segmentation fault might
       occur in a worker process; the bug had appeared in 0.8.33.
       Thanks to Yichun Zhang.

    *) Bugfix: IMAP connections may hang until they timed out while talking
       to Zimbra server.
       Thanks to Alan Batie.